Mounds Branch, Little Platte River Watershed (GP03)
Mounds Branch, Little Platte River Watershed (GP03)
Mounds Branch (947100)
4.45 Miles
0 - 4.45
Natural Community
Natural communities (stream and lake natural communities) represent model results that use predicted flow and temperature based on landscape features and related assumptions. Ranges of flow and temperature associated with specific aquatic life communities (fish, macroinvertebrates) help biologists identify appropriate resource management goals. Wisconsin Natural Communities.
Cool-Cold Headwater, Cool-Cold Mainstem
Year Last Monitored
This is the most recent date of monitoring data stored in SWIMS. Additional surveys for fish and habitat may be available subsequent to this date.
This river is impaired
Degraded Biological Community
Unknown Pollutant
Grant, Lafayette
Trout Water 
Trout Waters are represented by Class I, Class II or Class III waters. These classes have specific ecological characteristics and management actions associated with them. For more information regarding Trout Classifications, see the Fisheries Trout Class Webpages.
Outstanding or Exceptional 
Wisconsin has designated many of the state's highest quality waters as Outstanding Resource Waters (ORWs) or Exceptional Resource Waters (ERWs). Waters designated as ORW or ERW are surface waters which provide outstanding recreational opportunities, support valuable fisheries and wildlife habitat, have good water quality, and are not significantly impacted by human activities. ORW and ERW status identifies waters that the State of Wisconsin has determined warrant additional protection from the effects of pollution. These designations are intended to meet federal Clean Water Act obligations requiring Wisconsin to adopt an 'antidegradation' policy that is designed to prevent any lowering of water quality - especially in those waters having significant ecological or cultural value.
Impaired Water 
A water is polluted or 'impaired' if it does not support full use by humans, wildlife, fish and other aquatic life and it is shown that one or more of the pollutant criteria are not met.

Fish and Aquatic Life

Current Use
The use the water currently supports. This is not a designation or classification; it is based on the current condition of the water. Information in this column is not designed for, and should not be used for, regulatory purposes.
Fish and Aquatic Life - waters that do not have a specific use designation subcategory assigned but which are considered fishable, swimmable waters.
Attainable Use
The use that the investigator believes the water could achieve through managing "controllable" sources. Beaver dams, hydroelectric dams, low gradient streams, and naturally occurring low flows are generally not considered controllable. The attainable use may be the same as the current use or it may be higher.
Streams capable of supporting a warm waterdependent sport fishery. Representative aquatic life communities associated with these waters generally require cool or warm temperatures and concentrations of dissolved oxygen that do not drop below 5 mg/L.
Designated Use
This is the water classification legally recognized by NR102 and NR104, Wis. Adm. Code. The classification determines water quality criteria and effluent limits. Waters obtain designated uses through classification procedures.
Default FAL
Fish and Aquatic Life - Default Waters do not have a specific use designation subcategory but are considered fishable, swimmable waters.


This eight mile long stream has its origins in extreme northwest Lafayette and southwest Iowa counties. Historically the stream has had a minor smallmouth bass fishery. Poor agricultural practices including excessive grazing and erosion and barnyard runoff resulted in fi sh kills in the 1980’s. Monitoring in 2009 at a site just upstream from Sate Highway 80 showed the presence of smallmouth bass, as well as a diversity of cool-warm transitional forage species, including some very large specimens of common shiner and hornyhead chub. This section is still heavily pastured, with trampled banks and raw, slumping outside bends.

Date  2011

Author  James Amrhein


Mounds Branch is a tributary to the Little Platte River just outside of Platteville. The stream did have a minor smallmouth bass fishery, however, poor agricultural practices including excessive streambank grazing and erosion, and barnyard runoff resulted in fish kills and other water quality problems (Fix, 1991). The sources of the stream’s water quality problems were identified and the problems have since been cleaned up, however, no new monitoring data has been collected to determine if the game fishery has been restored. (Vollrath, 1998). New large-scale animal operations have been proposed in Mounds Branch sub-watershed. The siting of these operations and the waste management from these facilities will be an important issue in maintaining stream health. One species listed on the state’s threatened and endangered species list had historically been found along Mounds Branch (WDNR, 1997). This species is very sensitive to water pollution.

Date  2001

Author   Aquatic Biologist

Historical Description

A low-gradient, spring-fed stream beginning in Lafayette County near First Capitol State Park and flowing in a westerly direction to enter the Little Platte River two miles north of Platteville. A rubble and gravel bottom predominates, and moderate-sized pools are common within Grant County. The stream banks are severely eroded and overgrazing is a serious problem in the watershed. Several water retention structures have been built on intermittent tributaries in an effort to reduce these erosion problems. Smallmouth bass dominate the fishery, and forage fish are abundant. The better smallmouth bass fishing is found in the lower one mile of stream and fishing pressure is very light. Game assets include muskrats, mink, raccoon, squirrels, deer, and ruffed grouse. An occasional puddle duck can be seen during the spring and fall migratory periods. The stream is accessible from the Little Platte River and Highway 80. Only two dwellings are found along the banks in Grant County.

From: Smith, Tom D., and Ball, Joseph R., Lake and Stream Classification Project. Surface Water Resources of Grant County, Department of Natural Resources, 1972. Surface Area = 4.85 acres, Length = 4.0 miles, Gradient = 15 ft./mile, Flow = 6.5 c.f.s.

Date  1972

Author   Aquatic Biologist

Historical Description

Mounds Branch - Mouth location T4N RIE Section 18 -16, Surface area = 0.8 acres, Length = 0.8 miles, Gradient = 87.5 feet per mile, Total alkalinity = 281.0 mg/l, Volume of flow = 0.2 cfs.
The Mounds Branch begins in Iowa County where it is only 0.8 of a mile long and flows into Lafayette and Grant Counties where it becomes a good smallmouth bass stream. It is classified as a warmwater seepage stream with a very high gradient in Iowa County. This accounts for the rapid runoff of precipitation and heavy bank erosion. There is no sport fishery in Iowa County and only a token forage fishery is present. Aquatic game assets are also very limited. There are no public lands but it can be reached from a town road just over the Iowa-Lafayette County line.

From: Piening, Ronald and Threinen, C.W., 1968. Lake and Stream Classification Project. Surface Water Resources of Iowa County. Wisconsin Department of Natural Resources, Madison, WI

Date  1968

Author   Surface Water Inventory Of Wisconsin

Historical Description

Mounds Branch, T4N, R1W, Section 34-10, Surface acres = 3.1, Miles = 3.0, Gradient = 53.3 feet per mile, Total alkalinity = 281 mg/l, Volume of flow = 2.9 cfs.
As a warm water drainage stream it begins in Lafayette County and flowsinto Grant County where it joins the Little Platte River as one of its major tributaries. Approximately two-thirds of its base flow within the county is derived from three feeder streams. Bank erosion is a serious problem throughout most of its length. A small population of smallmouth bass constitutes the stream's sport fishery within the county. There is also an abundance of forage fishes. Gravel is the most common bottom type with silt being found occasionally on meander lobes. The principal vegetative cover on the banks and floodplain
is fresh meadow mixed with firm pasture. The upland cover throughout the watershed is mostly in farm crops with hardwoods common on the steeper slopes. Upland game species usually found in the county are common and some puddle ducks and muskrats are known to utilize the stream for food and shelter. There is no public land on the stream and access is restricted to one town road bridge near its headwaters.

From: Piening, Ronald; Poff, Ronald; Threinen, C.W., 1967. Lake and Stream Classification Project. Surface Water Resources of Lafayette County, Wisconsin Department of Natural Resources, Madison, WI.

Date  1967

Author   Surface Water Inventory Of Wisconsin

Mounds Branch, Little Platte River Watershed (GP03) Fish and Aquatic LifeMounds Branch, Little Platte River Watershed (GP03) RecreationMounds Branch, Little Platte River Watershed (GP03) Fish Consumption

Impaired Waters

The 2018 assessments of Mounds Branch (mouth to Unnamed Stream (WBIC 947600) near county line) showed biological impairment; new macroinvertebrate sample data exceeded the 2018 WisCALM listing criteria for the Fish and Aquatic Life use (i.e. at least one macroinvertebrate Index of Biotic Integrity (IBI) average scored in the poor condition category). Based on the most updated information, this water was proposed for the impaired waters list.

Date  2017

Author  Ashley Beranek


Wisconsin has over 84,000 miles of streams, 15,000 lakes and milllions of acres of wetlands. Assessing the condition of this vast amount of water is challenging. The state's water monitoring program uses a media-based, cross-program approach to analyze water condition. An updated monitoring strategy (2015-2020) is now available. Compliance with Clean Water Act fishable, swimmable standards are located in the Executive Summary of Water Condition in 2018. See also the 'monitoring and projects' tab.


Management Goals

Wisconsin's Water Quality Standards provide qualitative and quantitative goals for waters that are protective of Fishable, Swimmable conditions [Learn more]. Waters that do not meet water quality standards are considered impaired and restoration actions are planned and carried out until the water is once again fishable and swimmable

Management goals can include creation or implementation of a Total Maximum Daily Load analysis, a Nine Key Element Plan, or other restoration work, education and outreach and more. If specific recommendations exist for this water, they will be displayed below online.


Monitoring the condition of a river, stream, or lake includes gathering physical, chemical, biological, and habitat data. Comprehensive studies often gather all these parameters in great detail, while lighter assessment events will involve sampling physical, chemical and biological data such as macroinvertebrates. Aquatic macroinvertebrates and fish communities integrate watershed or catchment condition, providing great insight into overall ecosystem health. Chemical and habitat parameters tell researchers more about human induced problems including contaminated runoff, point source dischargers, or habitat issues that foster or limit the potential of aquatic communities to thrive in a given area. Wisconsin's Water Monitoring Strategy was recenty updated.

Grants and Management Projects

Monitoring Projects

Watershed Characteristics

Mounds Br is located in the Little Platte River watershed which is 154.94 miĀ². Land use in the watershed is primarily agricultural (46.20%), grassland (38%) and a mix of forest (10.40%) and other uses (5.50%). This watershed has 389.19 stream miles, 19.99 lake acres and 585.06 wetland acres.

Nonpoint Source Characteristics

This watershed is ranked High for runoff impacts on streams, Not Available for runoff impacts on lakes and High for runoff impacts on groundwater and therefore has an overall rank of High. This value can be used in ranking the watershed or individual waterbodies for grant funding under state and county programs.However, all waters are affected by diffuse pollutant sources regardless of initial water quality. Applications for specific runoff projects under state or county grant programs may be pursued. For more information, go to surface water program grants.

Natural Community

Mounds Branch is considered a Cool-Cold Headwater, Cool-Cold Mainstem under the state's Natural Community Determinations.

Natural communities (stream and lake natural communities) represent model resultsand DNR staff valiation processes that confirm or update predicted conditions based on flow and temperature modeling from historic and current landscape features and related variables. Predicated flow and temperatures for waters are associated predicated fish assemblages (communities). Biologists evaluate the model results against current survey data to determine if the modeled results are corect and whether biological indicators show water quaity degradation. This analysis is a core component of the state's resource management framework. Wisconsin's Riverine Natural Communities.

Cool (Cold-Transition) Mainstem streams are moderate-to-large but still wadeable perennial streams with cold to cool summer temperatures. Coldwater fishes are common to uncommon, transitional fishes are abundant to common, and warm water fishes are uncommon to absent. Headwater species are common to absent, mainstem species are abundant to common, and river species are common to absent.

Cool (Cold-Transition) Headwaters are small, usually perennial streams with cold to cool summer temperatures. Coldwater fishes are common to uncommon (<10 per 100 m), transitional fishes are abundant to common, and warm water fishes are uncommon to absent. Headwater species are abundant to common, mainstem species are common to absent, and river species are absent.